Electrical Tree Test Device for Silicone Rubber Cable Accessories
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrical tree test devices for silicone rubber materials in cable accessories face issues with uneven stress distribution, sample movement, and limited mechanical deformation capability, making it difficult to accurately test the electrical tree characteristics under mechanical stress, especially for thicker samples and high-voltage applications.
Innovation Solution
An electrical tree test device with a tensile test system featuring symmetrically arranged tensile members, a digital microscopic imaging system, and a method for preparing samples with semi-conductive electrodes, allowing for greater mechanical deformation and accurate simulation of electrical tree initiation and growth processes in silicone rubber samples.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a pressing rod with bolt is used to fix the sample, then the sample can be clamped, but the pressing rod rotates during fastening causing sample movement and uneven stress distribution
Solution Approach 1:
The pressing rod structure uses asymmetric design with a fixed end and a rotating end, where the rotating end can rotate relative to the rod body to accommodate sample thickness variations without causing rod rotation, thereby maintaining uniform stress distribution during clamping
Solution Approach 2:
The pressing rod structure is pre-designed with a rotating end that can independently rotate before contact, allowing the rod to self-align and prevent rotation during fastening, thus eliminating sample movement and ensuring uniform stress distribution from the beginning of the clamping process
2Ease of operation
If a groove structure is used to fix the sample, then the sample can be positioned, but the groove size restriction prevents thicker electrical tree samples from being placed
Solution Approach 1:
The pressing rod structure serves multiple functions: it can clamp samples of various thicknesses, position samples accurately, and accommodate both thin sheet samples and thick electrical tree samples through its rotating end mechanism, eliminating the need for different fixtures for different sample types
3Ease of manufacture
If steel needles are used as high-voltage electrodes, then the needle-plate electrode structure can be formed, but cracks and air gaps are easily generated at the needle tip under great mechanical deformation
Solution Approach 1:
The electrode structure uses a disposable or replaceable needle tip design where the vulnerable needle tip can be easily replaced if damaged, or the entire electrode assembly can be replaced after a certain number of tests, ensuring reliability without requiring complex protective mechanisms for each individual test
4Adaptability or versatility
If the sample is subjected to great mechanical deformation, then the electrical tree characteristic of deformed cable accessory can be reflected, but the steel needle electrode causes sample tearing at the tip
Solution Approach 1:
The sample is pre-mounted in a fixture that provides lateral support to the needle tip area before deformation begins, preventing sample tearing at the tip during the initial stages of deformation while still allowing great deformation ranges to be achieved
Data Source
AI summary
Provided are an electrical tree test device for a silicone rubber material for a cable accessory and a method for preparing a sample. The method includes: adding a semi-conductive silicone rubber into xylene, performing spraying on a surface of a silicone rubber insulation sample sheet, performing a curing processing, cutting the sample sheet into a high-voltage electrode with a triangular longitudinal section end, then adhering the high-voltage electrode on the surface of the silicone rubber insulation sample sheet, and performing a high temperature vulcanization to obtain a silicon rubber sample sheet; placing the silicon rubber sample sheet into a mold, injecting a high temperature vulcanizable liquid silicone rubber mixture, and performing the high temperature vulcanization, to obtain a sample; and performing cutting at a position distanced from a tip of the high-voltage electrode by 2 mm, and adhering a ground electrode of a flat plate-like structure at the cross section.